Nanomed-based Detection of Early Prostate Tumors

German investigators are trying to develop a novel imaging modality, based on detection of antibodies conjugated to gold nanoparticles, to be used for early diagnosis, and possible treatment, of prostate cancer.
From the press statement by the Fraunhofer Institute for Biomedical Engineering:

A novel, cost-efficient and sensitive device will soon increase the number of early diagnoses of prostate cancer and offer more patients the prospect of recovery. This diagnostic device was developed by researchers at the Fraunhofer Institute for Biomedical Technology IBMT in St. Ingbert in collaboration with partners from five European countries. The European Commission is funding the project to the tune of 2.2 million euros. “We use a combination of two different imaging techniques: optical imaging and ultrasound,” says IBMT department manager Dr. Robert Lemor. “We shine laser light into the tissue, causing it to heat up and expand. This generates pressure in the form of a sound wave, which spreads through the tissue in much the same way as ultrasound and is also detected in the same way.” The researchers thus combine the good contrast of light with the good spatial resolution of sound, using the advantages of both systems.
In order to detect cancer cells at an early stage, however, the researchers require an even stronger contrast between cancerous and healthy cells. “We achieve this by using gold particles just a few nanometers in size. Gold absorbs the laser’s infrared light much better than the cells, and therefore appears brighter in the picture,” says Lemor. The researchers attach antibodies to the gold particles, and these antibodies bond with specific proteins. These occur several thousand times more frequently in cancer cells than in healthy tissue. “This means that the gold accumulates specifically around the cancer cells, while hardly any gold is found on healthy cells,” explains Lemor. The gold particles not only serve diagnostic purposes but can also be used for therapy. If the laser output is increased and the tissue is irradiated for a longer period, the gold heats up and the generated heat destroys the cancer cells. Healthy tissue is not affected, as hardly any gold accumulates in it.